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Magnetic and Critical Properties of Alternating Spin Chain with S=1/2,1 in Magnetic Fields

Mitsuru Fujii·Satoshi Fujimoto·Norio Kawakami
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Abstract

We study an integrable spin chain with an alternating array of spins S=1/2, 1 in external magnetic fields using the Bethe ansatz exact solution. The calculated magnetization possesses a cusp structure at a critical magnetic field H=H_{C}, at which the specific heat shows a divergence property. We also calculate finite-size corrections to the energy spectrum, and obtain the critical exponents of correlation functions with the use of conformal field theory (CFT). Low-energy properties of the model are described by two c=1 U(1) CFTs in H H_{C}.

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Mitsuru Fujii, Satoshi Fujimoto, Norio Kawakami. 1996-11-05. Magnetic and Critical Properties of Alternating Spin Chain with S=1/2,1 in Magnetic Fields. https://doi.org/10.1143/jpsj.65.2381

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